铁死亡的发生机制及其在肺癌中的研究进展

铁死亡是近年来发现的一种铁依赖性的程序性细胞死亡,这种死亡是脂质过氧化物和活性氧堆积引起的。而肺癌作为病死率最高的恶性肿瘤之一,关于肺癌中铁死亡的研究甚少。本文中我们综述了肺癌中铁死亡受抑制的研究进展,从铁死亡发生的不同途径来解释肺癌中铁死亡受抑制现象。此外,诱导铁死亡治疗癌症越来越受到重视,本文中我们介绍了四种铁死亡激活剂以及铁死亡治疗肺癌的新展望,以期为肺癌治疗提供新的思路。

Kilowatt-level supercontinuum generation in a single-stage random fiber laser with a half-open cavity

The random distributed-feedback fiber laser(RFL) is a new approach to obtain a high-power stable supercontinuum(SC) source.To consider both structure simplification and high-power SC output,an innovative structure achieving a kilowatt-level SC output in a single-stage RFL with a half-open cavity is demonstrated in this paper.It consists of a fiber oscillator,a piece of long passive fiber and a broadband coupler,among which the broadband coupler acting as a feedback device is crucial in SC generation.When the system has no feedback,the backward output power is up to298 W under the pump power of 1185 W.When the feedback is introduced before the pump laser,the backward power loss can be reduced and the pump can be fully utilized,which could promote forward output power and conversion efficiency significantly.Under the maximum pump power of 1847 W,a 1300 W SC with spectrum ranging from 887 to1920 nm and SC conversion efficiency of 66% is obtained.To the best of our knowledge,it is the simplest structure used for high-power SC generation,and both the generated SC output power and the conversion efficiency are highest in the scheme of the half-opened RFL output SC.

Fabrication of titania thin film with composite nanostructure and its ability to photodegrade rhodamine B in water

A titania nanorod filmwas synthesized by direct oxidation of metallic Ti with hydrogen peroxide solution under a low temperature.Titania nanoparticles were then filled into the gaps among the nanorods through an infiltration sol-gel procedure to form a composite titania film with an ordered nanostructure.X-ray diffraction spectra indicate that the composite film was a mixture of anatase and rutile while the titania film obtained by only using a sol-gel procedure was pure anatase.Field emission scanning electron microscopy observations show that titania nanoparticles were embedded into the titania nanorod film.Photoluminescence spectra suggest the enhanced separation of electron and hole pairs for the obtained composite titania film over the corresponding titania nanorod film.The composite titania film exhibited improved ability to photodegrade rhodamine B in water compared with the titania nanorod film.The apparent photodegradation rate constant,fitting a pseudo-first-order,was 3 times of that obtained by the sol-gel derived titania film at the same weight.The improved photocata-lytic activity for the composite titania film could be attributed to the enhanced separation of electron and hole pairs due to the embedding of the titania nanoparticles within the titania nanorods.

CONSTRUCTION OF CUBATURE FORMULAS VIA BIVARIATE QUADRATIC SPLINE SPACES OVER NON-UNIFORM TYPE-2 TRIANGULATION

In this paper,matrix representations of the best spline quasi-interpolating operator over triangular sub-domains in S_(2)^(1)(△_(mn)^(2),and coefficients of splines in terms of B-net are calculated firstly.Moreover,by means of coefficients in terms of B-net,computation of bivariate numerical cubature over triangular sub-domains with respect to variables x and y is transferred into summation of coefficients of splines in terms of B-net.Thus concise bivariate cubature formulas are constructed over rectangular sub-domain.Furthermore,by means of module of continuity and max-norms,error estimates for cubature formulas are derived over both sub-domains and the domain.

Phase Characterization and Formation Behavior in 6 wt%Si High-silicon Austenitic Stainless Steel during Isothermal Aging

The precipitation behavior of different phases in a high-silicon stainless steel(6 wt%Si)during aging at 600–1050℃for24 h was investigated.The morphology,crystal structure and composition of various precipitates were detailly characterized using optical microscopy,scanning electron microscopy and transmission electron microscopy.Four phases were mainly identified:χ-phase,M_6C carbides,σphase and a new type of fcc-phase.During aging at 600–900℃,the main precipitate was(Cr,Mo and Si)-richχ-phase which was directly precipitated fromγmatrix.Theχ-phase was calibrated as bcc structure with a lattice parameter of 8.90?.The peak temperature for the precipitation ofχ-phase was 800℃,and it was dissolved when aging at temperatures above 1000℃.Theσ-phase was observed only at 700℃and grew next toχ-phase.Above 700℃,a new fcc-phase was found to be precipitated along withχ-phase,with a space group of Fd3c and a lattice parameter of 12.56?.The M_6C carbides started to be precipitated at 700℃in the vicinity ofχ-phase.And its amount basically increased with the increasing of temperature.An orientation relationship between M_6C/γwas found:[100]c//[100]γ,(001)c//(001)γ,i.e.,the cube-on-cube relationship.

Geochronology,petrogenesis,and geological significance of the quartz vein-type copper deposits in Longwei area,north-west Dayaoshan,Guangxi

Quartz-vein-type copper deposits were discovered in SN-trend ore-bearing structures in north-west Dayaoshan,Guangxi.Lack of reports on the precise metallogenic age of these deposit has become a bottleneck in metallogenic research in this area.In this study,the quartz vein-type copper mine in Longwei area of Jinxiu was selected as the research object.Fresh illite samples in the fault gouges and ore samples were collected for testing and analysis.Based on the Re-Os isotope dating study,the age of pyrite isochron,belonging to the Caledonian period,was determined to be 417±25 Ma,whereas that of chalcopyrite isochron belonging to the Indosinian period,was found to be 243±18 Ma.Pyrite crystallized considerably earlier than chalcopyrite.The obtained EPMA data were combined with rock mineralogical analysis data,Metasomatous mineral pyrite and metasomatic mineral chalcopyrite were identified to have originated from different hydrothermal systems.In the Indosinian period,copper deposits in the Longwei area underwent pyrite crystallization,pyrite fragmentation,copper-bearing hydrothermal filling,and metasomatism,consolidating and forming minerals.The study determined the mineralisation time and ore sources of copper deposits in the Longwei area.The study provides evidence for the existence of Indosinian hydrothermal activities in the north-western Dayaoshan area.